Next Generation Gravity Mission (NGGM) implementation status and scientific outlook

The Next Generation Gravity Mission (NGGM) is European Space Agency’s (ESA) next Mission of Opportunity.  It aims to extend and improve time series of satellite gravity missions by providing enhanced spatial and temporal resolution time-varying gravity field measurements with reduced uncertainty and latency to address the international user needs as expressed by the International Union of Geodesy and Geophysics (IUGG[1]) and the Global Climate Observing System (GCOS[2]) and demonstrate the critical capabilities for a potential future operational gravity mission.MAss Change and Geosciences International Constellation (MAGIC) is the European Space Agency (ESA) and National Aeronautics and Space Administration (NASA) jointly developed concept for collaboration on future satellite gravity constellation that addresses the needs of the international user community. MAGIC will consist of the GRACE-C (NASA and German Aerospace Center (DLR)) and NGGM (ESA) staggered deployment of 2 satellite pairs, with progressively improving measurement performance, to form a Bender-type constellation. GRACE-C will continue the successful US-German partnership of GRACE and GRACE-FO, building on important European technologies to ensure continuity and global coverage of observations. NGGM will advance the technology and scientific innovation and will enable the demonstration of applications and operational capabilities for both NGGM and MAGIC, for a panoply of applications critical for climate change monitoring and Earth sciences, e.g. Hydrology, Climate Change, Cryosphere, Oceanography, Solid Earth and Geodesy. NGGM will fly in a lower altitude (~400km), controlled inclined orbit at 70 degrees, with the objective to deliver consistent, quality-assured data products with enhanced high spatial (~150 km) and temporal (sub-weekly) resolutions as well as reduced latency compared to the present state-of-the-art.This paper provides a status overview of the NGGM implementation, including the on-going B1-B2 bridging phase system and technology pre-development activities. It also presents the scientific perspective of NGGM and MAGIC, detailing their respective science and mission objectives, mission performance metrics, recent algorithmic advancements for NGGM and MAGIC, as well as the anticipated impact on scientific research and applications arising from ESA’s NGGM Phase B1 science studies.[1] Pail, R., Bingham, R., Braitenberg, C. et al. Science and User Needs for Observing Global Mass Transport to Understand Global Change and to Benefit Society. Surv Geophys 36, 743–772 (2015). https://doi.org/10.1007/s10712-015-9348-9[2] Terrestrial Water Storage ECV Requirements: The 2022 GCOS ECVs Requirements (GCOS 245)